Answer:
<em>The valid conclusion is:</em>
- <u><em>D. the temperature of the object is increasing, while the temperature of the water is decreasing</em></u>
<u><em></em></u>
Explanation:
The answer choices are:
- <em>A. the temperature of the object is decreasing, while the temperature of the water is increasing</em>
- <em>B. the temperature of the object is decreasing, while the temperature of the water is decreasing</em>
- <em>C. the temperature of the object is increasing, while the temperature of the water is increasing</em>
- <em>D. the temperature of the object is increasing, while the temperature of the water is decreasing</em>
<em />
<h2>Solution</h2>
<em />
Thermal or heat energy always flows from the hotter substances to the cooler substances.
Thus, since the arrows show that the thermal energy is flowing from the water to the object, the water is losing thermal energy and the object is gaining thermal energy.
When an object gains thermal energy, and there is not involved a change of phase, the temperature of the object increases. Thus, the temperature of the object is increasing.
On the other hand, since water is losing thermal energy, and there is not involved a change of phase, the temperature of the water decreases.
Therefore, the correct conclusion is described by the option A:
- <em>A. the temperature of the object is decreasing, while the temperature of the water is increasing</em>
Fill in the blanks in order w/ these numbers:
1. 2 1 2 1
2. 3 1 1
3. 1 2 1 2
4. 2 1 1
5. 4 3 2
6. 1 1 2
Hope this helps.
Answer:
At lower temperatures the solubility of the KCl decreased and recrystallization occurred
Explanation:
Solubility refers to the amount of solute that dissolves in one litre of water at a particular temperature. Solubility is a property referring to the ability for a given substance, the solute, to dissolve in a solvent. It is measured in terms of the maximum amount of solute dissolved in a solvent at equilibrium. The resulting solution is called a saturated solution.
Solubility is dependent on temperature. This is the reason why we must state the particular temperature at which a given solubility data was collected. Above or below the quoted temperature, the solubility data may no longer be accurate.
Let's return to the question, at elevated temperatures, we can see that the KCl is very soluble in water as evidenced by the clear solution obtained at high temperature. However, as the temperature decreases, the solubility of KCl also decreases accordingly and recrystallization of the solute occurred hence the formation of a cloudy solution and the settling of some solid at the bottom of the flask.
Answer:81.6%
Explanation:
Mass of CaCO3=4.010 g
Molar mass of CaCO3= 40+12+(16×3) = 100 g/mol.
Recall: number of moles(n)= mass÷ molar mass.
n=4.010÷100 = 0.0401 mol.
Molar mass of CaCl2 = 40+71= 111 g/mol.
Number of mol of CaCl2 = 5.455÷111= 0.04914 g/mol.
Mass of CaCl2 = 0.0401 × 111 = 4.4511 g of CaCl2.
Percent by mass of CaCl2 = (4.4511÷5.455) × 100
= 0.815967 ×100 = 81.5967%
Approximately; 81.6%.
18 percent of x will be equal to 12 percent of y
